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[PMID]:28841378
[Au] Autor:Hollingsworth SA; Nguyen BD; Chreifi G; Arce AP; Poulos TL
[Ad] Endereço:Department of Molecular Biology and Biochemistry, University of California , Irvine, California 92697, United States.
[Ti] Título:Insights into the Dynamics and Dissociation Mechanism of a Protein Redox Complex Using Molecular Dynamics.
[So] Source:J Chem Inf Model;57(9):2344-2350, 2017 Sep 25.
[Is] ISSN:1549-960X
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Leishmania major peroxidase (LmP) is structurally and functionally similar to the well-studied yeast Cytochrome c peroxidase (CCP). A recent Brownian dynamics study showed that L. major Cytochrome c (LmCytc) associates with LmP by forming an initial complex with the N-terminal helix A of LmP, followed by a movement toward the electron transfer (ET) site observed in the LmP-LmCytc crystal structure. Critical to forming the active electron transfer complex is an intermolecular Arg-Asp ion pair at the center of the interface. If the dissociation reaction is effectively the reverse of the association reaction, then rupture of the Asp-Arg ion pair should be followed by movement of LmCytc back toward LmP helix A. To test this possibility, we have performed multiple molecular dynamics (MD) simulations of the LmP-LmCytc complex. In five separate simulations, LmCytc is observed to indeed move toward helix A, and in two of the simulations, the Asp-Arg ion pair breaks, which frees LmCytc to fully associate with the LmP helix A secondary binding site. These results support the "bind and crawl" or "velcro" mechanism of association, wherein LmCytc forms a nonspecific electrostatic complex with LmP helix A, followed by a "crawl" toward the ET-active site, where the Asp-Arg ion pair holds the LmCytc in position for rapid ET. These simulations also point to Tyr134 as being important in the association/dissociation reactions. Experimentally mutating Tyr134 to Phe was found to decrease K by 3.6-fold, which is consistent with its predicted role in complex formation by MD simulations.
[Mh] Termos MeSH primário: Citocromo-c Peroxidase/química
Citocromo-c Peroxidase/metabolismo
Leishmania major/enzimologia
Simulação de Dinâmica Molecular
Peroxidase/química
Peroxidase/metabolismo
[Mh] Termos MeSH secundário: Heme/metabolismo
Mutação
Oxirredução
Peroxidase/genética
Conformação Proteica
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
42VZT0U6YR (Heme); EC 1.11.1.5 (Cytochrome-c Peroxidase); EC 1.11.1.7 (Peroxidase)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171107
[Lr] Data última revisão:
171107
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170826
[St] Status:MEDLINE
[do] DOI:10.1021/acs.jcim.7b00421


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[PMID]:28542725
[Au] Autor:Dantas JM; Brausemann A; Einsle O; Salgueiro CA
[Ad] Endereço:UCIBIO-Requimte, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, Caparica, Portugal.
[Ti] Título:NMR studies of the interaction between inner membrane-associated and periplasmic cytochromes from Geobacter sulfurreducens.
[So] Source:FEBS Lett;591(12):1657-1666, 2017 Jun.
[Is] ISSN:1873-3468
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Geobacter sulfurreducens is a dissimilatory metal-reducing bacterium with notable properties and significance in biotechnological applications. Biochemical studies suggest that the inner membrane-associated diheme cytochrome MacA and the periplasmic triheme cytochrome PpcA from G. sulfurreducens can exchange electrons. In this work, NMR chemical shift perturbation measurements were used to map the interface region and to measure the binding affinity between PpcA and MacA. The results show that MacA binds to PpcA in a cleft defined by hemes I and IV, favoring the contact between PpcA heme IV and the MacA high-potential heme. The dissociation constant values indicate the formation of a low-affinity complex between the proteins, which is consistent with the transient interaction observed in electron transfer complexes.
[Mh] Termos MeSH primário: Citocromo-c Peroxidase/metabolismo
Citocromos c/metabolismo
Geobacter/enzimologia
Heme/metabolismo
Proteínas de Membrana/metabolismo
Modelos Moleculares
Proteínas Periplásmicas/metabolismo
[Mh] Termos MeSH secundário: Algoritmos
Proteínas de Bactérias/química
Proteínas de Bactérias/genética
Proteínas de Bactérias/metabolismo
Sítios de Ligação
Cristalografia por Raios X
Citocromo-c Peroxidase/química
Citocromo-c Peroxidase/genética
Citocromos c/química
Citocromos c/genética
Bases de Dados de Proteínas
Transporte de Elétrons
Heme/química
Cinética
Proteínas de Membrana/química
Proteínas de Membrana/genética
Simulação de Acoplamento Molecular
Isótopos de Nitrogênio
Ressonância Magnética Nuclear Biomolecular
Oxirredução
Proteínas Periplásmicas/química
Proteínas Periplásmicas/genética
Conformação Proteica
Domínios e Motivos de Interação entre Proteínas
Multimerização Proteica
Proteínas Recombinantes/química
Proteínas Recombinantes/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Membrane Proteins); 0 (Nitrogen Isotopes); 0 (Periplasmic Proteins); 0 (Recombinant Proteins); 42VZT0U6YR (Heme); 9007-43-6 (Cytochromes c); EC 1.11.1.5 (Cytochrome-c Peroxidase)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170925
[Lr] Data última revisão:
170925
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170526
[St] Status:MEDLINE
[do] DOI:10.1002/1873-3468.12695


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[PMID]:28087802
[Au] Autor:Zapata C; Paillavil B; Chávez R; Álamos P; Levicán G
[Ti] Título:Cytochrome c peroxidase (CcP) is a molecular determinant of the oxidative stress response in the extreme acidophilic Leptospirillum sp. CF-1.
[So] Source:FEMS Microbiol Ecol;93(3), 2017 Mar 01.
[Is] ISSN:1574-6941
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Bioleaching processes are used to recover metals from sulfidic ores. Biofilm formation on ores is important for bioleaching because the attached microorganisms start the leaching process by concentrating ferric ions in the extracellular matrix. It has been shown that hydrogen peroxide is spontaneously generated on the surface of ores and that it negatively influences the growth and activity of microorganisms. However, the mechanism by which bioleaching microorganisms tolerate exogenous H2O2 as an adaptive trait remains elusive. Herein, we demonstrate that the gene yhjA, encoding a predicted periplasmic cytochrome c peroxidase (CcP), is important for the response to exogenously generated oxidative stress in the iron-oxidizing acidophilic bacterium Leptospirillum sp. CF-1. Our results show that yhjA is co-transcribed with the genes encoding the peroxide-responsive transcription regulator PerR and peroxiredoxin AhpC. CcP activity, but not yhjA mRNA level, significantly increased in response to hydrogen peroxide and ferric ion exposure, suggesting a post-translational regulation. In agreement with these results, challenging planktonic cells with hydrogen peroxide significantly increased their attachment to pyrite surfaces. In summation, our results suggest that CcP is important to cope with exogenous H2O2, thus favoring the early steps of attachment to mineral substrates.
[Mh] Termos MeSH primário: Bactérias/genética
Citocromo-c Peroxidase/metabolismo
Estresse Oxidativo/genética
[Mh] Termos MeSH secundário: Citocromo-c Peroxidase/genética
Peróxido de Hidrogênio
Ferro
Oxirredução
Sulfetos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Sulfides); 132N09W4PR (pyrite); BBX060AN9V (Hydrogen Peroxide); E1UOL152H7 (Iron); EC 1.11.1.5 (Cytochrome-c Peroxidase)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170822
[Lr] Data última revisão:
170822
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170115
[St] Status:MEDLINE
[do] DOI:10.1093/femsec/fix001


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[PMID]:27860106
[Au] Autor:Hewitt SH; Filby MH; Hayes E; Kuhn LT; Kalverda AP; Webb ME; Wilson AJ
[Ad] Endereço:School of Chemistry, University of Leeds, Woodhouse Lane, Leeds, LS2 9JT, UK.
[Ti] Título:Protein Surface Mimetics: Understanding How Ruthenium Tris(Bipyridines) Interact with Proteins.
[So] Source:Chembiochem;18(2):223-231, 2017 Jan 17.
[Is] ISSN:1439-7633
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:Protein surface mimetics achieve high-affinity binding by exploiting a scaffold to project binding groups over a large area of solvent-exposed protein surface to make multiple cooperative noncovalent interactions. Such recognition is a prerequisite for competitive/orthosteric inhibition of protein-protein interactions (PPIs). This paper describes biophysical and structural studies on ruthenium(II) tris(bipyridine) surface mimetics that recognize cytochrome (cyt) c and inhibit the cyt c/cyt c peroxidase (CCP) PPI. Binding is electrostatically driven, with enhanced affinity achieved through enthalpic contributions thought to arise from the ability of the surface mimetics to make a greater number of noncovalent interactions than CCP with surface-exposed basic residues on cyt c. High-field natural abundance H, N HSQC NMR experiments are consistent with surface mimetics binding to cyt c in similar manner to CCP. This provides a framework for understanding recognition of proteins by supramolecular receptors and informing the design of ligands superior to the protein partners upon which they are inspired.
[Mh] Termos MeSH primário: Complexos de Coordenação/metabolismo
Citocromo-c Peroxidase/metabolismo
Citocromos c/metabolismo
Rutênio/química
[Mh] Termos MeSH secundário: 2,2'-Dipiridil/química
Complexos de Coordenação/síntese química
Complexos de Coordenação/química
Citocromo-c Peroxidase/antagonistas & inibidores
Citocromo-c Peroxidase/genética
Citocromos c/antagonistas & inibidores
Citocromos c/genética
Concentração de Íons de Hidrogênio
Espectroscopia de Ressonância Magnética
Concentração Osmolar
Ligação Proteica
Domínios e Motivos de Interação entre Proteínas
Proteínas Recombinantes/biossíntese
Proteínas Recombinantes/química
Proteínas Recombinantes/isolamento & purificação
Espectrometria de Fluorescência
Eletricidade Estática
Propriedades de Superfície
Termodinâmica
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Coordination Complexes); 0 (Recombinant Proteins); 551W113ZEP (2,2'-Dipyridyl); 7UI0TKC3U5 (Ruthenium); 9007-43-6 (Cytochromes c); EC 1.11.1.5 (Cytochrome-c Peroxidase)
[Em] Mês de entrada:1705
[Cu] Atualização por classe:170510
[Lr] Data última revisão:
170510
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161119
[St] Status:MEDLINE
[do] DOI:10.1002/cbic.201600552


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[PMID]:27664317
[Au] Autor:Melin F; Xie H; Meyer T; Ahn YO; Gennis RB; Michel H; Hellwig P
[Ad] Endereço:Laboratoire de Bioélectrochimie et Spectroscopie, Chimie de la Matière Complexe, UMR 7140, Université de Strasbourg, 1 Rue Blaise Pascal, 67000 Strasbourg, France.
[Ti] Título:The unusual redox properties of C-type oxidases.
[So] Source:Biochim Biophys Acta;1857(12):1892-1899, 2016 12.
[Is] ISSN:0006-3002
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Cytochrome cbb (also known as C-type) oxidases belong to the family of heme-copper terminal oxidases which couple at the end of the respiratory chain the reduction of molecular oxygen into water and the pumping of protons across the membrane. They are expressed most often at low pressure of O and they exhibit a low homology of sequence with the cytochrome aa (A-type) oxidases found in mitochondria. Their binuclear active site comprises a high-spin heme b associated with a Cu center. The protein also contains one low-spin heme b and 3 hemes c. We address here the redox properties of cbb oxidases from three organisms, Rhodobacter sphaeroides, Vibrio cholerae and Pseudomonas stutzeri by means of electrochemical and spectroscopic techniques. We show that the redox potential of the heme b exhibits a relatively low midpoint potential, as in related cytochrome c-dependent nitric oxide reductases. Potential implications for the coupled electron transfer and proton uptake mechanism of C-type oxidases are discussed.
[Mh] Termos MeSH primário: Proteínas de Bactérias/metabolismo
Complexo IV da Cadeia de Transporte de Elétrons/metabolismo
Oxigênio/metabolismo
Pseudomonas stutzeri/enzimologia
Rhodobacter sphaeroides/enzimologia
Vibrio cholerae/enzimologia
[Mh] Termos MeSH secundário: Proteínas de Bactérias/química
Citocromo-c Peroxidase/metabolismo
Transporte de Elétrons
Complexo IV da Cadeia de Transporte de Elétrons/química
Heme/metabolismo
Ligações de Hidrogênio
Ligantes
Potenciais da Membrana
Oxirredução
Oxirredutases/metabolismo
Potenciometria
Ligação Proteica
Conformação Proteica
Prótons
Espectrofotometria Ultravioleta
Espectroscopia de Infravermelho com Transformada de Fourier
Relação Estrutura-Atividade
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Ligands); 0 (Protons); 42VZT0U6YR (Heme); EC 1.- (Oxidoreductases); EC 1.11.1.5 (Cytochrome-c Peroxidase); EC 1.7.2.5 (nitric-oxide reductase); EC 1.9.3.- (cbb3 oxidase); EC 1.9.3.1 (Electron Transport Complex IV); S88TT14065 (Oxygen)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170807
[Lr] Data última revisão:
170807
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160925
[St] Status:MEDLINE


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[PMID]:27586347
[Au] Autor:Bhagi-Damodaran A; Hosseinzadeh P; Mirts E; Reed J; Petrik ID; Lu Y
[Ad] Endereço:University of Illinois at Urbana-Champaign, Urbana, IL, United States.
[Ti] Título:Design of Heteronuclear Metalloenzymes.
[So] Source:Methods Enzymol;580:501-37, 2016.
[Is] ISSN:1557-7988
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Heteronuclear metalloenzymes catalyze some of the most fundamentally interesting and practically useful reactions in nature. However, the presence of two or more metal ions in close proximity in these enzymes makes them more difficult to prepare and study than homonuclear metalloenzymes. To meet these challenges, heteronuclear metal centers have been designed into small and stable proteins with rigid scaffolds to understand how these heteronuclear centers are constructed and the mechanism of their function. This chapter describes methods for designing heterobinuclear metal centers in a protein scaffold by giving specific examples of a few heme-nonheme bimetallic centers engineered in myoglobin and cytochrome c peroxidase. We provide step-by-step procedures on how to choose the protein scaffold, design a heterobinuclear metal center in the protein scaffold computationally, incorporate metal ions into the protein, and characterize the resulting metalloproteins, both structurally and functionally. Finally, we discuss how an initial design can be further improved by rationally tuning its secondary coordination sphere, electron/proton transfer rates, and the substrate affinity.
[Mh] Termos MeSH primário: Heme/química
Metaloproteínas/química
Mioglobina/química
Engenharia de Proteínas/métodos
[Mh] Termos MeSH secundário: Catálise
Citocromo-c Peroxidase/química
Heme/síntese química
Íons/química
Metaloproteínas/síntese química
Metais/química
Oxirredução
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Ions); 0 (Metalloproteins); 0 (Metals); 0 (Myoglobin); 42VZT0U6YR (Heme); EC 1.11.1.5 (Cytochrome-c Peroxidase)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170807
[Lr] Data última revisão:
170807
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160903
[St] Status:MEDLINE


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[PMID]:27499202
[Au] Autor:Payne TM; Yee EF; Dzikovski B; Crane BR
[Ad] Endereço:Department of Chemistry and Chemical Biology, Cornell University , Ithaca, New York 14853, United States.
[Ti] Título:Constraints on the Radical Cation Center of Cytochrome c Peroxidase for Electron Transfer from Cytochrome c.
[So] Source:Biochemistry;55(34):4807-22, 2016 Aug 30.
[Is] ISSN:1520-4995
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The tryptophan 191 cation radical of cytochrome c peroxidase (CcP) compound I (Cpd I) mediates long-range electron transfer (ET) to cytochrome c (Cc). Here we test the effects of chemical substitution at position 191. CcP W191Y forms a stable tyrosyl radical upon reaction with peroxide and produces spectral properties similar to those of Cpd I but has low reactivity toward reduced Cc. CcP W191G and W191F variants also have low activity, as do redox ligands that bind within the W191G cavity. Crystal structures of complexes between Cc and CcP W191X (X = Y, F, or G), as well as W191G with four bound ligands reveal similar 1:1 association modes and heme pocket conformations. The ligands display structural disorder in the pocket and do not hydrogen bond to Asp235, as does Trp191. Well-ordered Tyr191 directs its hydroxyl group toward the porphyrin ring, with no basic residue in the range of interaction. CcP W191X (X = Y, F, or G) variants substituted with zinc-porphyrin (ZnP) undergo photoinduced ET with Cc(III). Their slow charge recombination kinetics that result from loss of the radical center allow resolution of difference spectra for the charge-separated state [ZnP(+), Cc(II)]. The change from a phenyl moiety at position 191 in W191F to a water-filled cavity in W191G produces effects on ET rates much weaker than the effects of the change from Trp to Phe. Low net reactivity of W191Y toward Cc(II) derives either from the inability of ZnP(+) or the Fe-CcP ferryl to oxidize Tyr or from the low potential of the resulting neutral Tyr radical.
[Mh] Termos MeSH primário: Citocromo-c Peroxidase/química
Citocromo-c Peroxidase/metabolismo
Citocromos c/química
Citocromos c/metabolismo
[Mh] Termos MeSH secundário: Substituição de Aminoácidos
Sítios de Ligação/genética
Cátions/química
Cristalografia por Raios X
Citocromo-c Peroxidase/genética
Transporte de Elétrons
Radicais Livres/química
Cinética
Ligantes
Modelos Moleculares
Mutagênese Sítio-Dirigida
Processos Fotoquímicos
Conformação Proteica
Proteínas Recombinantes/química
Proteínas Recombinantes/genética
Proteínas Recombinantes/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Cations); 0 (Free Radicals); 0 (Ligands); 0 (Recombinant Proteins); 9007-43-6 (Cytochromes c); EC 1.11.1.5 (Cytochrome-c Peroxidase)
[Em] Mês de entrada:1705
[Cu] Atualização por classe:171118
[Lr] Data última revisão:
171118
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160809
[St] Status:MEDLINE
[do] DOI:10.1021/acs.biochem.6b00262


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[PMID]:27270708
[Au] Autor:Seal M; Ghosh C; Basu O; Dey SG
[Ad] Endereço:Department of Inorganic Chemistry, Indian Association for the Cultivation of Science, Jadavpur, Kolkata, 700032, India.
[Ti] Título:Cytochrome c peroxidase activity of heme bound amyloid ß peptides.
[So] Source:J Biol Inorg Chem;21(5-6):683-90, 2016 Sep.
[Is] ISSN:1432-1327
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:Heme bound amyloid ß (Aß) peptides, which have been associated with Alzheimer's disease (AD), can catalytically oxidize ferrocytochrome c (Cyt c(II)) in the presence of hydrogen peroxide (H2O2). The rate of catalytic oxidation of Cyt(II) c has been found to be dependent on several factors, such as concentration of heme(III)-Aß, Cyt(II) c, H2O2, pH, ionic strength of the solution, and peptide chain length of Aß. The above features resemble the naturally occurring enzyme cytochrome c peroxidase (CCP) which is known to catalytically oxidize Cyt(II) c in the presence of H2O2. In the absence of heme(III)-Aß, the oxidation of Cyt(II) c is not catalytic. Thus, heme-Aß complex behaves as CCP.
[Mh] Termos MeSH primário: Peptídeos beta-Amiloides/metabolismo
Citocromo-c Peroxidase/metabolismo
Heme/metabolismo
[Mh] Termos MeSH secundário: Peptídeos beta-Amiloides/química
Citocromo-c Peroxidase/química
Heme/química
Peróxido de Hidrogênio/química
Peróxido de Hidrogênio/metabolismo
Cinética
Análise Espectral Raman
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Amyloid beta-Peptides); 42VZT0U6YR (Heme); BBX060AN9V (Hydrogen Peroxide); EC 1.11.1.5 (Cytochrome-c Peroxidase)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:171013
[Lr] Data última revisão:
171013
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160609
[St] Status:MEDLINE
[do] DOI:10.1007/s00775-016-1367-6


  9 / 662 MEDLINE  
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[PMID]:27262052
[Au] Autor:Wang J
[Ad] Endereço:Department of Molecular Biophysics and Biochemistry, Yale University, Connecticut 06520, New Haven.
[Ti] Título:Destruction-and-diffraction by X-ray free-electron laser.
[So] Source:Protein Sci;25(9):1585-92, 2016 Sep.
[Is] ISSN:1469-896X
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:It is common knowledge that macromolecular crystals are damaged by the X-rays they are exposed to during conventional data collection. One of the claims made about the crystallographic data collection now being collected using X-ray free-electron lasers (XFEL) is that they are unaffected by radiation damage. XFEL data sets are assembled by merging data obtained from a very large number of crystals, each of which is exposed to a single femtosecond pulse of radiation, the duration of which is so short that diffraction occurs before the damage done to the crystal has time to become manifest, i.e. "diffraction-before-destruction." However, recent theoretical studies have shown that many of the elemental electronic processes that ultimately result in the destruction of such crystals occur during a single pulse. It is predicted that the amplitudes of atomic scattering factor could be reduced by as much as 75% within the first 5 femtoseconds of such pulses, and that different atoms will respond in different ways. Experimental evidence is provided here that these predictions are correct.
[Mh] Termos MeSH primário: Citocromo-c Peroxidase/química
Complexo IV da Cadeia de Transporte de Elétrons/química
Elétrons
Lasers
Complexo de Proteína do Fotossistema II/química
Espalhamento de Radiação
[Mh] Termos MeSH secundário: Domínios Proteicos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Photosystem II Protein Complex); EC 1.11.1.5 (Cytochrome-c Peroxidase); EC 1.9.3.1 (Electron Transport Complex IV)
[Em] Mês de entrada:1707
[Cu] Atualização por classe:170902
[Lr] Data última revisão:
170902
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160605
[St] Status:MEDLINE
[do] DOI:10.1002/pro.2959


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[PMID]:27070578
[Au] Autor:de Visser SP; Stillman MJ
[Ad] Endereço:Manchester Institute of Biotechnology and School of Chemical Engineering and Analytical Science, the University of Manchester, 131 Princess Street, Manchester M1 7DN, UK. sam.devisser@manchester.ac.uk.
[Ti] Título:Challenging Density Functional Theory Calculations with Hemes and Porphyrins.
[So] Source:Int J Mol Sci;17(4):519, 2016 Apr 07.
[Is] ISSN:1422-0067
[Cp] País de publicação:Switzerland
[La] Idioma:eng
[Ab] Resumo:In this paper we review recent advances in computational chemistry and specifically focus on the chemical description of heme proteins and synthetic porphyrins that act as both mimics of natural processes and technological uses. These are challenging biochemical systems involved in electron transfer as well as biocatalysis processes. In recent years computational tools have improved considerably and now can reproduce experimental spectroscopic and reactivity studies within a reasonable error margin (several kcal·mol(-1)). This paper gives recent examples from our groups, where we investigated heme and synthetic metal-porphyrin systems. The four case studies highlight how computational modelling can correctly reproduce experimental product distributions, predicted reactivity trends and guide interpretation of electronic structures of complex systems. The case studies focus on the calculations of a variety of spectroscopic features of porphyrins and show how computational modelling gives important insight that explains the experimental spectra and can lead to the design of porphyrins with tuned properties.
[Mh] Termos MeSH primário: Heme/química
Porfirinas/química
[Mh] Termos MeSH secundário: Animais
Sistema Enzimático do Citocromo P-450/química
Citocromo-c Peroxidase/química
Complexo IV da Cadeia de Transporte de Elétrons/química
Elétrons
Hemeproteínas/química
Hemoglobina A/química
Seres Humanos
Metaloporfirinas/química
Modelos Moleculares
Conformação Proteica
Teoria Quântica
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T; REVIEW
[Nm] Nome de substância:
0 (Hemeproteins); 0 (Metalloporphyrins); 0 (Porphyrins); 42VZT0U6YR (Heme); 9034-51-9 (Hemoglobin A); 9035-51-2 (Cytochrome P-450 Enzyme System); EC 1.11.1.5 (Cytochrome-c Peroxidase); EC 1.9.3.1 (Electron Transport Complex IV)
[Em] Mês de entrada:1612
[Cu] Atualização por classe:170220
[Lr] Data última revisão:
170220
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160413
[St] Status:MEDLINE



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